OTRC: Mariah Carey and Nick Cannon debut twins on '20/20' - See Video

Mariah Carey and Nick Cannon debuted their baby twins Moroccan and Monroe on an episode of "20/20," set to air on October 21.

The six-month-old twins, who go by "Roc and Roe" at home and "dem babies" on Carey's Twitter have been hidden from public view until now. Carey and Cannon sat down with Barbara Walters to introduce the tots and to discuss their struggles conceiving, the singer's high-risk pregnancy, parenthood and their marriage.

Though the couple are joyful parents now, the process of conceiving was fraught with difficulties, including a miscarriage. With the help of fertility treatments, the couple welcomed their twins in April.

"I don't think I understood the enormity or the magnitude of what it really does to your body," the Grammy-winning singer said in a promo for the episode. "Like it's not just, oh you don't look pretty and you have a bump."

Carey, 41, and Cannon welcomed their twins Moroccan and Monroe on April 30 via Caesarean section. The date also marked the couple's second wedding anniversary.

Carey's rep said that they were listening to Carey's "We Belong Together" when the children were born. The twins are couple's first children together and Carey recently declared that she doesn't intend to have more.

On Easter, Carey posted a photo of her belly, which sported a colorful, painted picture of a butterfly, one of her favorite symbols and the name of her sixth studio album, which came out in 1997. The words "Dem Babies" were painted above the butterfly.

Mariah Carey and Nick Cannon's "20/20" interview will air at 10 p.m. ET on ABC. Watch a promo below.